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arXiv · 1312.0123

Observation of quasiperiodic dynamics in a one-dimensional quantum walk of single photons in space

Peng Xue·Hao Qin·Bao Tang·Barry C. Sanders
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Abstract

We realize quasi-periodic dynamics of a quantum walker over 2.5 quasi-periods by realizing the walker as a single photon passing through a quantum-walk optical-interferometer network. We introduce fully controllable polarization-independent phase shifters in each optical path to realize arbitrary site-dependent phase shifts, and we employ large clear-aperture beam displacers, while maintaining high-visibility interference, to enable reaching 10 quantum-walk steps. By varying the half-wave-plate setting, we control the quantum-coin bias thereby observing a transition from quasi-periodic dynamics to ballistic diffusion.

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Peng Xue, Hao Qin, Bao Tang, Barry C. Sanders. 2013-11-30. Observation of quasiperiodic dynamics in a one-dimensional quantum walk of single photons in space. https://doi.org/10.1088/1367-2630/16/5/053009

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